1. Field of the Invention.
The present invention relates to a boost converter, and more particularly, to boost converters used with electronic ballasts for high intensity discharge lamps.
2. Description of the Related Art.
Ionized lamps, such as H.I.D. (high intensity discharge) lamps, use electronic ballasts that convert the public network's 50/60 Hz A.C. supply to a D.C. source and then through an inverter back to A.C. at a considerably higher frequency to drive the lamp. An inductor is used to limit the current through the lamp and this inductor is smaller for high frequencies. Thus, the desirability (lower weight, cost) of operating with high frequencies through the use of an electronic inverter.
Typically, the voltage of the corrector circuit is twice the input voltage which makes it necessary to use additional control circuitry requiring the use of additional active elements such as transistors and integrated circuits. The patents issued to Richard C. Counts under U.S. Pat. No. 5,051,662 and to Bryce L. Hesterman under U.S. Pat. No. 5,568,041, are such examples.
Other patents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention.